AppArmor: basic auditing infrastructure.

Update lsm_audit for AppArmor specific data, and add the core routines for
AppArmor uses for auditing.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <jmorris@namei.org>

2 files changed, 338 insertions, 0 deletions

diff --git a/security/apparmor/audit.c b/security/apparmor/audit.c
new file mode 100644
index 000000000000..96502b22b268
--- /dev/null
+++ b/security/apparmor/audit.c
@@ -0,0 +1,215 @@
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor auditing functions
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2010 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ */
+
+#include <linux/audit.h>
+#include <linux/socket.h>
+
+#include "include/apparmor.h"
+#include "include/audit.h"
+#include "include/policy.h"
+
+const char *op_table[] = {
+        "null",
+
+        "sysctl",
+        "capable",
+
+        "unlink",
+        "mkdir",
+        "rmdir",
+        "mknod",
+        "truncate",
+        "link",
+        "symlink",
+        "rename_src",
+        "rename_dest",
+        "chmod",
+        "chown",
+        "getattr",
+        "open",
+
+        "file_perm",
+        "file_lock",
+        "file_mmap",
+        "file_mprotect",
+
+        "create",
+        "post_create",
+        "bind",
+        "connect",
+        "listen",
+        "accept",
+        "sendmsg",
+        "recvmsg",
+        "getsockname",
+        "getpeername",
+        "getsockopt",
+        "setsockopt",
+        "socket_shutdown",
+
+        "ptrace",
+
+        "exec",
+        "change_hat",
+        "change_profile",
+        "change_onexec",
+
+        "setprocattr",
+        "setrlimit",
+
+        "profile_replace",
+        "profile_load",
+        "profile_remove"
+};
+
+const char *audit_mode_names[] = {
+        "normal",
+        "quiet_denied",
+        "quiet",
+        "noquiet",
+        "all"
+};
+
+static char *aa_audit_type[] = {
+        "AUDIT",
+        "ALLOWED",
+        "DENIED",
+        "HINT",
+        "STATUS",
+        "ERROR",
+        "KILLED"
+};
+
+/*
+ * Currently AppArmor auditing is fed straight into the audit framework.
+ *
+ * TODO:
+ * netlink interface for complain mode
+ * user auditing, - send user auditing to netlink interface
+ * system control of whether user audit messages go to system log
+ */
+
+/**
+ * audit_base - core AppArmor function.
+ * @ab: audit buffer to fill (NOT NULL)
+ * @ca: audit structure containing data to audit (NOT NULL)
+ *
+ * Record common AppArmor audit data from @sa
+ */
+static void audit_pre(struct audit_buffer *ab, void *ca)
+{
+        struct common_audit_data *sa = ca;
+        struct task_struct *tsk = sa->tsk ? sa->tsk : current;
+
+        if (aa_g_audit_header) {
+                audit_log_format(ab, "apparmor=");
+                audit_log_string(ab, aa_audit_type[sa->aad.type]);
+        }
+
+        if (sa->aad.op) {
+                audit_log_format(ab, " operation=");
+                audit_log_string(ab, op_table[sa->aad.op]);
+        }
+
+        if (sa->aad.info) {
+                audit_log_format(ab, " info=");
+                audit_log_string(ab, sa->aad.info);
+                if (sa->aad.error)
+                        audit_log_format(ab, " error=%d", sa->aad.error);
+        }
+
+        if (sa->aad.profile) {
+                struct aa_profile *profile = sa->aad.profile;
+                pid_t pid;
+                rcu_read_lock();
+                pid = tsk->real_parent->pid;
+                rcu_read_unlock();
+                audit_log_format(ab, " parent=%d", pid);
+                if (profile->ns != root_ns) {
+                        audit_log_format(ab, " namespace=");
+                        audit_log_untrustedstring(ab, profile->ns->base.hname);
+                }
+                audit_log_format(ab, " profile=");
+                audit_log_untrustedstring(ab, profile->base.hname);
+        }
+
+        if (sa->aad.name) {
+                audit_log_format(ab, " name=");
+                audit_log_untrustedstring(ab, sa->aad.name);
+        }
+}
+
+/**
+ * aa_audit_msg - Log a message to the audit subsystem
+ * @sa: audit event structure (NOT NULL)
+ * @cb: optional callback fn for type specific fields (MAYBE NULL)
+ */
+void aa_audit_msg(int type, struct common_audit_data *sa,
+                  void (*cb) (struct audit_buffer *, void *))
+{
+        sa->aad.type = type;
+        sa->lsm_pre_audit = audit_pre;
+        sa->lsm_post_audit = cb;
+        common_lsm_audit(sa);
+}
+
+/**
+ * aa_audit - Log a profile based audit event to the audit subsystem
+ * @type: audit type for the message
+ * @profile: profile to check against (NOT NULL)
+ * @gfp: allocation flags to use
+ * @sa: audit event (NOT NULL)
+ * @cb: optional callback fn for type specific fields (MAYBE NULL)
+ *
+ * Handle default message switching based off of audit mode flags
+ *
+ * Returns: error on failure
+ */
+int aa_audit(int type, struct aa_profile *profile, gfp_t gfp,
+             struct common_audit_data *sa,
+             void (*cb) (struct audit_buffer *, void *))
+{
+        BUG_ON(!profile);
+
+        if (type == AUDIT_APPARMOR_AUTO) {
+                if (likely(!sa->aad.error)) {
+                        if (AUDIT_MODE(profile) != AUDIT_ALL)
+                                return 0;
+                        type = AUDIT_APPARMOR_AUDIT;
+                } else if (COMPLAIN_MODE(profile))
+                        type = AUDIT_APPARMOR_ALLOWED;
+                else
+                        type = AUDIT_APPARMOR_DENIED;
+        }
+        if (AUDIT_MODE(profile) == AUDIT_QUIET ||
+            (type == AUDIT_APPARMOR_DENIED &&
+             AUDIT_MODE(profile) == AUDIT_QUIET))
+                return sa->aad.error;
+
+        if (KILL_MODE(profile) && type == AUDIT_APPARMOR_DENIED)
+                type = AUDIT_APPARMOR_KILL;
+
+        if (!unconfined(profile))
+                sa->aad.profile = profile;
+
+        aa_audit_msg(type, sa, cb);
+
+        if (sa->aad.type == AUDIT_APPARMOR_KILL)
+                (void)send_sig_info(SIGKILL, NULL, sa->tsk ? sa->tsk : current);
+
+        if (sa->aad.type == AUDIT_APPARMOR_ALLOWED)
+                return complain_error(sa->aad.error);
+
+        return sa->aad.error;
+}
diff --git a/security/apparmor/include/audit.h b/security/apparmor/include/audit.h
new file mode 100644
index 000000000000..1951786d32e9
--- /dev/null
+++ b/security/apparmor/include/audit.h
@@ -0,0 +1,123 @@
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor auditing function definitions.
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2010 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ */
+
+#ifndef __AA_AUDIT_H
+#define __AA_AUDIT_H
+
+#include <linux/audit.h>
+#include <linux/fs.h>
+#include <linux/lsm_audit.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+
+#include "file.h"
+
+struct aa_profile;
+
+extern const char *audit_mode_names[];
+#define AUDIT_MAX_INDEX 5
+
+#define AUDIT_APPARMOR_AUTO 0   /* auto choose audit message type */
+
+enum audit_mode {
+        AUDIT_NORMAL,           /* follow normal auditing of accesses */
+        AUDIT_QUIET_DENIED,     /* quiet all denied access messages */
+        AUDIT_QUIET,            /* quiet all messages */
+        AUDIT_NOQUIET,          /* do not quiet audit messages */
+        AUDIT_ALL               /* audit all accesses */
+};
+
+enum audit_type {
+        AUDIT_APPARMOR_AUDIT,
+        AUDIT_APPARMOR_ALLOWED,
+        AUDIT_APPARMOR_DENIED,
+        AUDIT_APPARMOR_HINT,
+        AUDIT_APPARMOR_STATUS,
+        AUDIT_APPARMOR_ERROR,
+        AUDIT_APPARMOR_KILL
+};
+
+extern const char *op_table[];
+enum aa_ops {
+        OP_NULL,
+
+        OP_SYSCTL,
+        OP_CAPABLE,
+
+        OP_UNLINK,
+        OP_MKDIR,
+        OP_RMDIR,
+        OP_MKNOD,
+        OP_TRUNC,
+        OP_LINK,
+        OP_SYMLINK,
+        OP_RENAME_SRC,
+        OP_RENAME_DEST,
+        OP_CHMOD,
+        OP_CHOWN,
+        OP_GETATTR,
+        OP_OPEN,
+
+        OP_FPERM,
+        OP_FLOCK,
+        OP_FMMAP,
+        OP_FMPROT,
+
+        OP_CREATE,
+        OP_POST_CREATE,
+        OP_BIND,
+        OP_CONNECT,
+        OP_LISTEN,
+        OP_ACCEPT,
+        OP_SENDMSG,
+        OP_RECVMSG,
+        OP_GETSOCKNAME,
+        OP_GETPEERNAME,
+        OP_GETSOCKOPT,
+        OP_SETSOCKOPT,
+        OP_SOCK_SHUTDOWN,
+
+        OP_PTRACE,
+
+        OP_EXEC,
+        OP_CHANGE_HAT,
+        OP_CHANGE_PROFILE,
+        OP_CHANGE_ONEXEC,
+
+        OP_SETPROCATTR,
+        OP_SETRLIMIT,
+
+        OP_PROF_REPL,
+        OP_PROF_LOAD,
+        OP_PROF_RM,
+};
+
+
+/* define a short hand for apparmor_audit_data portion of common_audit_data */
+#define aad apparmor_audit_data
+
+void aa_audit_msg(int type, struct common_audit_data *sa,
+                  void (*cb) (struct audit_buffer *, void *));
+int aa_audit(int type, struct aa_profile *profile, gfp_t gfp,
+             struct common_audit_data *sa,
+             void (*cb) (struct audit_buffer *, void *));
+
+static inline int complain_error(int error)
+{
+        if (error == -EPERM || error == -EACCES)
+                return 0;
+        return error;
+}
+
+#endif /* __AA_AUDIT_H */